Alcohol and allergy

An ‘adverse food reaction’ is a term which refers to any unpleasant reaction to a food or beverage. This adverse food reaction may be immunologically or non-immunologically based. A food allergy is due to your immune system, anything else is a food intolerance.

Basically, a food allergy is where a normally harmless substance is seen as a threat by the body’s immunological defences. As concerns alcohol, even light drinking can cause an allergic reaction. Allergic reactions can include migraine headaches, itchiness, rashes, bowel colic, diarrhoea, asthma, swollen facial features and watery swollen eyes.

Many consumers think that the main cause of an adverse reaction to wine is due to sulphur dioxide, which is an antioxidant and preservative. Unless you have a similar reaction when eating dried fruits, such as dried apricots, this is unlikely as the concentration of sulphur dioxide will be much higher in the dried fruits than in the wine.

Histamine is commonly believed to be a main cause of an adverse reaction to wine, possibly due to its relatively high concentration in certain wines, although many foods such as aubergine, tomatoes and fish contain a significantly higher concentration than wine. However, we think substances in wine may induce the release of histamine from mast cells or certain individuals may have a reduced activity and/or amount of one of the enzymes that break down histamine in the intestine. Histamine-related symptoms are similar to those of food allergy.

A recent study has assessed adverse reactions to histamine in wine in 16 individuals, who were intolerant to wine. No correlation was observed between the concentration of histamine in wine and an adverse reaction. However, the consumption of wines, which had a low concentration of histamine increased the blood concentration of histamine in these individuals by 10 minutes post-consumption, which suggests that there may be histamine-releasing chemicals in wine.

Asthma

If asthma is triggered by sulphur compounds, then fermented beverages should not be consumed as SO2 is used as a preservative and is a natural by product of fermentation. If the asthma is not triggered by sulphur compounds, then alcoholic drinks are unlikely to trigger an asthma attack.

If you are ‘sulphite-sensitive’, drinks that contain a lower concentration of sulphur dioxide are recommended. For example, wines labelled as ‘made with organic grapes’ contain approximately 50% less sulphur dioxide than bag in box wines.

Ethnic differences

Some Asians have an ‘inactive’ gene for breaking down alcohol, this means that acetaldehyde (the toxin from the break down of alcohol) builds up in the bloodstream and liver. The blood concentration of this toxin in individuals with the inactive gene can be 10-times higher than normal. The physical effects can include facial flushing, a rapid heartbeat, a headache, nausea and vomiting, extreme drowsiness or tiredness and low blood pressure. The effects of any drinking are so unpleasant that most people with the inactive gene won’t drink alcohol.

Hangover?

An adverse reaction or allergy is not to be confused with excessive alcohol consumption. If an individual drinks sensibly, ideally with food and follows government guidelines, they will not suffer the side effects of ‘over’ consumption.

A hangover is where one develops headache, nausea, vomiting, lethargy, and a dry mouth due to excessive alcohol consumption. It is due to dehydration especially of the brain cells, which temporarily shrink. The reason one becomes dehydrated is because of the osmotic pressure and diuretic effects of alcohol.

The way to prevent a hangover is to drink less alcohol and drink plenty of water or soft drinks whilst consuming alcohol. It is advisable to start a meal or a party with a soft drink then have one after each alcoholic drink.

Binge drinking is the most harmful way of drinking. Binge drinking is characterised by drinking lightly, or perhaps not at all during the week, but 'saving up' consumption for heavy bouts of alcohol drinking at the weekend, often on an empty stomach.

Recent surveys show that people who binge (that is over 5-6 alcoholic drinks or 40-48g alcohol at any one time) completely negate the protective effect of alcohol against coronary heart disease, even if moderation is practiced at other times.

Please visit the gateway to sensible drinking and health, alcoholinmoderation.com for specific studies and summary papers.